Telemetry devices have been successfully utilized in automated meter reading (AMR) applications. In such applications, a telemetry device typically transmits utility usage information to remote data collection modules which, in turn, transmit the information back, often over the Internet, to a central data collection facility. Telemetry devices are typically transmit-only devices in order to keep costs low and reduce power consumption.
The telemetry devices typically transmit data on a timed basis or on the occurrence of an event, such as a pulse received from the meter being read. An AMR system may utilize multiple data collection modules that may receive a transmission from the same telemetry device, in an effort to enhance reliability of data transmissions. An arbitration scheme may be utilized to determine which data collection module receiving data from the same telemetry device forwards the data to the central data collection facility. Further, data may be transmitted multiple times in an effort to ensure at least one of the transmissions is successfully received by a data collection module.
While transmit-only telemetry devices may be adequate for AMR applications, they suffer a number of disadvantages compared to two-way telemetry devices. First, transmit-only telemetry devices do not allow for two-way handshaking between the transmitting device and the receiving device. Two-way handshaking may increase reliability of data transmissions. Further, a transmit-only telemetry device may not be polled by another telemetry device. Finally, a transmit-only telemetry device may not receive useful information from another telemetry device, such as information regarding the strength of signals transmitted from the transmit-only telemetry device.